1. Field of the Invention
The present invention relates to a pattern controller of a shotshell which controls the shot pattern of a shotshell.
2. Description of Related Art
In a conventional shotgun, the barrel thereof is usually provided therein with a choke to control the distribution density (pattern) of a shotpellets at a predetermined shooting range. A full-choke barrel which is provided, in the vicinity of the muzzle, with a great degree of choke to concentrate the shotpellets can be advantageously used for a long-range shooting, such as a trap shooting. On the other hand, a barrel having a negative choke, i.e., a skeet choke in which the muzzle is slightly enlarged to scatter the shotpellets, is usually used for a short-range shooting, such as skeet shooting.
There are intermediate several degrees of choke, including an improved cylinder barrel, a recess choked barrel or a true cylinder barrel (which has no choke because the choked portion has disappeared because of cutting away the choked front end portion of the barrel to shorten the length of the barrel). For instance, the improved cylinder barrel which is provided with a small amount of choke (a little choke) put therein is widely used by many hunters.
Note that the improved cylinder barrel, the recess choked barrel, and the true cylinder barrel will be generally referred to as a cylinder bore barrel hereinafter.
As can be understood from the foregoing, in the prior art, a remarkable function to concentrate or scatter shotpellets to be fired from a muzzle has mainly relied on the choke of the barrel, with a few exceptions.
The primary object of the present invention is to provide a pattern controller which can be loaded in a shotshell to realize a more extremely concentrated or scattered pattern than conventional commercially available shotshells even if the shotshell having the pattern controller incorporated therein is fired from a skeet choke or a cylinder bore barrel.